Parkinson’s Disease. It is a real, everyday battle for those who have it – but the disease did not receive prompt attention until actor Michael J. Fox pronounced his diagnosis publicly in the 1990s.

Who knew that this week’s loss in actor Robin Williams would bring Parkinson’s Disease to the forefront once again?

There were many who said that Robin Williams died of depression, while reports surfaced claiming that it is likely his drug rehab return (after having some small victory) is what led to him taking his own life. The wife of Robin Williams, however, says that her husband had Parkinson’s Disease – and that he did not want to disclose it, nor was he yet willing to talk about it.

“Robin’s sobriety was intact and he was brave as he struggled with his own battles of depression, anxiety as well as early stages of Parkinson’s Disease, which he was not yet ready to share publicly,” wife Susan Schneider told USA Today.

Parkinson’s Disease is characterized by an attack on the brain and nervous system. It can start with a quiver of the hand, or even a tremor of the body, which can then erupt into full-blown depression. It is this depression, a by-product of PD, that can make someone more prone to suicide and elevate a person’s risk for a suicide death.

Immediately after Schneider confirmed her husband’s diagnosis, actor Michael J. Fox tweeted, “Stunned to learn that Robin had PD. Pretty sure his support for our Fdn predated his diagnosis. A true friend; I wish him peace.”

Robin Williams died Monday but was discovered Monday afternoon when his secretary barged into his room to find out why the actor had not contacted her. Williams’s wife went to work early that morning, thinking that her husband, upon getting home late, had gone to bed late and was merely sleeping. Robin Williams was known for his roles in “Jumanji,” “Mrs. Doubtfire,” “Good Morning Vietnam,” “Dead Poet’s Society,” “Flubber,” his role as the Genie in “Aladdin,” and his television appearance in Law and Order: SVU, among others. He was 63 years old.